iPad Music App Not Working

We can't figure out how to get a student's iPad 2 to allow its music apps (Touch Bells, Drumline HD) to work so that he can play in band rehearsals. We can get a song downloaded with Drumline HD to play but the instruments themselves are not working.

We have also attempted to use iPhone apps (Cowbells Plus and a host of others) to work as well since the developers have listed iPad- and in some cases iPad 2- as appropriate for the programs.

Is there something we are missing that may enable us to get these applications to be active for him?